(a) Field of the Invention
The present invention generally relates to a liquid crystal display and a driving method thereof.
(b) Description of the Related Art
A liquid crystal display (“LCD”) is a widely used type of flat panel displays. The LCD typically includes two sheets of display panels which a field generating electrode, such as a pixel electrode and a common electrode, for example, is formed thereon and a liquid crystal layer is formed therebetween. The LCD generates an electric field in a liquid crystal layer by applying voltage to a field generating electrode, determines a direction of liquid crystal molecules of a liquid crystal layer, and controls polarization of incident light, thereby displaying images.
An LCD generally includes a pixel including a switching element constituted by a thin film transistor (“TFT”) that is a three-terminal element, a display panel including a display signal line such as a gate line and a data line, for example.
A liquid crystal layer typically includes a liquid crystal material having refractive anisotropy. Due to the refractive anisotropy of the liquid crystal material, a change in color and a change in contrast become substantially large according to a viewing angle. Thus, when a viewing angle is smaller, side visibility may be substantially degraded compared with front visibility. In order to solve the problem, a method of dividing one pixel electrode into two sub-pixel electrodes and applying different voltages to the two sub-pixel electrodes, for example, has been proposed. Each sub-pixel electrode is connected to a first switching element that switches applied voltage.
In order to apply different voltages to the two sub-pixel electrodes, one of two sub-pixel electrodes is connected to a transformation capacitor through a second switching element that is a three terminal element.
The first switching element and the second switching element may be controlled using a gate line. However, when a period where the first switching element is turned-on and a period where the second switching element is turned-on overlap with each other, there may be a problem of charging the sub-pixel electrode connected to the second switching element. Further, when signal lines other than gate lines are implemented on a display panel to control the second switching element, transmittance of the display panel is reduced, such that there is a problem of substantially degrading a value of commodities.